Tube heater for engine block



FIG. 1 is a top perspective view of a tube heater for engine block showing my new design;

FIG. 2 is a front end view thereof;

FIG. 3 is a rear end view thereof as seen from the left in FIG. 1;

FIG. 4 is a side elevation view thereof;

FIG. 5 is a side elevation view thereof, opposite the side shown in FIG. 4; and,

FIG. 6 is a bottom plan view thereof.

The broken line showing is for illustrative purposes only and is not considered part of the claimed design. 

The ornamental design for a tube heater for engine block, as shown and described. 